Hello,

Just joined/first post.

This has been a very interesting topic. My questions mostly are directed to TC. I know in Sikorsky's newest Navy H-60 there has been a large problem with cracking of the overhead load beam - the one that supports the engines, transmission, and rotor head. One solution has been the installation of a titanium beam. I know that great emphasis has been put on insulating the beam from any other metal - especially aluminum. This is due (so I'm told) to the fact that Titanium will exponentially speed up corrosion of other metals it is in contact with. I remember a comment about "frequency" or that they are so far apart on the “galvanic” scale or something like that. Because of this there has been numerous different inspections required to make sure the titanium stays insulated. I would wonder how, in an automotive setup with titanium components, other components in continual contact with the titanium pieces/parts would fare.

Also, if I remember correctly from a structures class I had to take, this particular lesson on fatigue - steel is the lone metal in which the “fatigue life” (cycles to failure) is indefinite as long as the cycles stay below the stress limit (s-n diagram-?). Titanium has a similar quality but I believe it only has an indefinite fatigue life if the stresses are only “half-cyclic” meaning the stresses flex the part only one way. So what I am getting at is a titanium axle housing would eventually get stress cracks because it is flexing both ways. I know that steel can crack as well but that is because it has experienced a stress level beyond its strength limit(taking it over some “sweet jumps”).

Anything anyone could expound or correct me on I would appreciate.

Clay

 

They should just use JB Weld--that stuff works awsome--just tried it the other day and i cant believe i havent ever used that stuff before.